Will their charter succeed in improving model health, after previous initiatives failed? It is too early to say. But the move is encouraging evidence of how fashion is being gradually democratised.

Social media has provided a platform for less powerful industry players â models, and consumer critics â who were effectively locked out of an elitist world in which designers dictated how women should look but accepted no accountability for the physical demands placed by a 23in waistband. With power comes responsibility. Finally, fashion is facing that maxim.

But there is more to unpick here about fashionâs internal power balance. A decade ago, designers at Paris fashion week were treated as deities; it would have been unrealistic for company bosses to dictate which models they should use. But in the six years since John Galliano dragged the name of Christian Dior into disrepute, the luxury giants have largely reined in the power and status of the designers they hire.

Talented, dependable, down-to-earth design studio veterans are now first in line for the top jobs, not eccentrics and mavericks. And while the de facto clout of designers has waned, the power of models has rocketed. Todayâs top catwalk models command commercial leverage of which 1990s supermodels could only have dreamt. (Linda Evangelista, famously, didnât get out of bed for less than Â£10,000; todayâs Insta-models could charge a designer pyjama brand ten times that to post a selfie on Instagram, without getting up.)

The momentum behind the LVMH-Kering charter came partly from the most fashionable power-couple in Paris: Antoine Arnault of LVMH and his supermodel wife Natalia Vodianova. Arnault referred to Vodianova in announcing the charter, saying: âMy wife â¦ said all these problems already existed 15 years ago, except that models didnât have social networks to talk about them and try to effect change â¦ We can really thank social networks for lifting the lid on a lot of things we would not have tolerated in the past if they had been public knowledge.â

The significance of the charter is that it moves on a debate that had long been muted by endless buck-passing. Models say casting agents demand tiny measurements; casting agents respond by saying that the sample sizes produced for the catwalk require them. Readers criticise magazines for showcasing skinny models; editors reciprocate by arguing that anything outside of the supermodel aesthetic causes newsstand sales to plunge. Consumers speak of feeling pressurised to diet by images of very thin models; models report that they have been trolled or body-shamed for being skinny.

Fashion did not invent size zero â the phrase emerged in LA in the early 1990s to describe the desired shape of aspiringHollywood actors. And negative body image is a problem that extends far beyond the Paris catwalks. But just as fashion is part of the problem, it must be part of the solution.

Francois-Henri Pinault of Kering has taken the bold step of drawing a direct link between fashion and anorexia. âA lot of people know â as I do â people affected by the scourge of anorexia,â he told Womenswear Daily. âThis represents an important advance in tackling the issue of excessive thinness and in particular anorexia in our profession.â

Accepting that responsibility lies with brands, this charter is not penalising women for being thin, but cracking down on an industry in which catwalk samples are produced in sizes that require already-slim women to starve themselves.